2 (a) The structure of an alcohol is shown in Figure 2 - AQA - GCSE Chemistry - Question 2 - 2014 - Paper 3
Question 2
2 (a) The structure of an alcohol is shown in Figure 2.
2 (a) (i) Draw a circle around the functional group in the structure of the alcohol.
2 (a) (ii) What is the... show full transcript
Worked Solution & Example Answer:2 (a) The structure of an alcohol is shown in Figure 2 - AQA - GCSE Chemistry - Question 2 - 2014 - Paper 3
Step 1
2 (a) (i) Draw a circle around the functional group in the structure of the alcohol.
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The functional group in the structure of the alcohol is the hydroxyl group (-OH). A circle should be drawn around this group in the structure presented in Figure 2.
Step 2
2 (a) (ii) What is the chemical name of this alcohol?
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The chemical name of this alcohol is ethanol.
Step 3
2 (b) (i) Suggest two ways that this apparatus could be improved to obtain accurate results.
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Add a lid to the beaker to reduce heat loss due to evaporation.
Insulate the beaker by wrapping it with a material that will minimize heat loss, ensuring that the majority of heat is retained within the water.
Step 4
2 (b) (ii) Describe how the student should do this experiment.
98%
120 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Experimental Method to Measure Energy Released by Alcohol
Equipment Setup
The student should set up the apparatus as shown in Figure 3, ensuring all components are correctly assembled.
Step-by-Step Procedure
Measure the initial mass of the alcohol (ethanol) in the burner using a precise balance.
Fill a beaker with a known volume of water and measure its initial temperature with a thermometer.
Position the alcohol burner beneath the beaker filled with water.
Light the alcohol and allow it to burn for a fixed period of time, ensuring that adequate stirring and ventilation are maintained.
After the heating period, measure the final temperature of the water and the mass of the alcohol burner again.
Calculate the change in temperature of the water and the mass lost from the alcohol to find the energy released per gram of alcohol burned.